1. Field of the Invention
The present invention relates to a dentition image reading apparatus. More specifically, it relates to a dentition image reading apparatus for directly taking a picture of upper jaw dentition and lower jaw dentition from inside of mouth to obtain an entire image of the dentition.
2. Description of Related Art
Conventionally, a roentgenography has been widely used as an indispensable tool for obtaining image in dental medical treatment. However, in recent years, digital cameras and small CCD cameras have come to be used for the purpose of explaining to a patient.
For instance, an image pick-up device having a hand holder including an image sensor and optical fibers arranged in ring-shape around the image sensor has been proposed in Japanese Utility Model Application Publication No. Hei 6-28859.
In Japanese Patent Laid-Open Publication No. Hei 9-140664, a dental in-mouth observation camera having a light guide and a CCD sensor provided on a distal head of a hand piece has been proposed.
However, since the above apparatuses only partially take a picture of the tooth to be treated and the image of the entire dentition cannot be taken, a treatment-requiring portion, and relationship between the treatment-requiring portion and the normal portion cannot be recognized.
In order to obtain an image of the entire dentition, a xe2x80x9cprocess and device for measuring the dimensions of a space, in particular a buccal cavityxe2x80x9d disclosed in international Patent Publication No. WO91/13586, and a xe2x80x9cdentition image reading apparatusxe2x80x9d disclosed in Japanese Utility Model Registration No. 3056089 have been known.
In the former xe2x80x9cmeasuring method of in-mouth space and an apparatus for implementing the methodxe2x80x9d, a light beam from a light source is irradiated to a tooth in mouth through a deflecting device and the reflecting light from the tooth is transmitted to an image pick-up device through the deflecting device.
The latter xe2x80x9cdentition image reading apparatusxe2x80x9d accommodates an image sensor and a light source in a transparent container inserted in mouth and the dentition image is obtained while moving the image sensor and the light source within the transparent container.
However, former method for obtaining the entire image of the dentition, the xe2x80x9cmeasuring method of in-mouth space and an apparatus for implementing the methodxe2x80x9d, requires a deflecting device of complicated structure and production cost thereof is difficult to be reduced.
Further, since the latter xe2x80x9cdentition image reading apparatusxe2x80x9d accommodates the image sensor and the light source within the transparent container inserted into mouth, the size of the transparent container is increased and therefore is difficult to be used for a child.
An object of the present invention is to provide a dentition image reading apparatus capable of reducing size and cost thereof and capable of reading the entire image of the dentition with high accuracy. In order to achieve the above object, the dentition image reading apparatus according to the present invention includes following arrangement.
A dentition image reading apparatus according to the present invention includes: an in-mouth insert to be inserted in a mouth having an upper jaw dentition and a lower jaw dentition; and image pick-up optics, the in-mouth insert having a light-transmitting portion at least on one of front and back sides thereof and a hollow portion provided thereinside, the image pick-up optics having: a light source inserted in the hollow portion in the in-mouth insert for irradiating light on the dentition through the light-transmitting portion; a reflection mirror for reflecting the light from the dentition toward the outside of the in-mouth insert; a scanner for moving the light source and the reflection mirror along the depth direction of the hollow portion of the in-mouth insert; and an image pick-up optical system for receiving the light reflected by the reflection mirror.
According to the above arrangement, after inserting the in-mouth insert into mouth, the light source and the reflection mirror is positioned at a predetermined position in the hollow portion of the in-mouth insert by the scanner, where the light from the light source reaches to the dentition through the light-transmitting portion to be reflected by the dentition and, consequently reaches to the image pick-up optical system through the reflection mirror. In other words, the dentition image data of the line where the light source and the reflection mirror located is retrieved. Next, the light source and the reflection mirror are stopped by the scanner after a predetermined distance movement, the dentition image data at the position is retrieved. In the same manner, the light source and the reflection mirror are moved by a predetermined distance and the dentition image data at respective positions is retrieved, which is combined to obtain an entire image of the dentition.
Accordingly, the external shape, evenness, color and dimension of the tooth can be facilitated, which enables to determine treatment, record growth of a child, determine whether orthodontics is required or not, and determine whether orthodontics wiring is required or not in a quantitative manner, and further, enables to efficiently collect dentition image at a mass check-up.
Especially, since only the light source and the reflection mirror are accommodated in the hollow portion of the in-mouth insert to be inserted to mouth, the size thereof can be reduced as compared to a conventional arrangement having a transparent container accommodating the image sensor and the light source. Further, since the image is obtained by receiving light reflected by the reflection mirror by the image pick-up optical system, the production cost can be reduced as compared to the conventional image pick-up device having a deflecting device.
The dentition image reading apparatus according to the above aspect of the present invention may preferably have a slant angle adjuster for adjusting a slant angle of the reflection mirror.
Ordinarily, when the slant angle of the reflection mirror relative to perpendicular direction is 45 degrees, the light reflected by right below the upper jaw dentition or right above the lower jaw dentition enters into the image pick-up optical system, whereby the images taken from right below or right above the dentition are synthesized.
According to the above arrangement, since the slant angle adjuster for adjusting the slant angle of the reflection mirror is provided, the obliquely-seen perspective dentition image can be obtained. Therefore, an image seen from the most viewable direction can be obtained even for a dentition of complicated structure.
In the present invention, the image pick-up optical system may preferably include: an image sensor; a lens for forming an image of the light reflected by the reflection mirror on a light-receiving surface of the image sensor; and a light-shield provided between the lens and the reflection mirror for preventing the light from the light source from directly entering into the image sensor.
According to the above arrangement, since the image pick-up optical system has the image sensor and the lens for focusing the light reflected by the reflection mirror on the light-receiving surface of the image sensor and the light-shield is disposed between the lens and the reflection mirror, the light directly entering from the light source into the image sensor can be removed to the utmost, thereby obtaining more vivid image.
In the present invention, the scanner may preferably include: a scanning base supporting the light source and the reflection mirror at a distal end thereof and supporting the image pick-up optical system at a base end thereof; a guide for movably guiding the scanning base along a depth direction of the hollow portion of the in-mouth insert; and a drive unit for moving the scanning base for every predetermined pitch.
According to the above arrangement, since the scanning base having the light source and the reflection mirror at a distal end thereof and having the image pick-up optical system at a base end thereof is movably guided along the depth direction of the hollow portion of the in-mouth insert and is moved for a predetermined pitch by the drive unit, the dentition image in mouth can be accurately obtained for every predetermined pitch.
In the present invention, the in-mouth insert may preferably have the light-transmitting portion respectively on the front and back sides thereof, and the image pick-up optics may preferably include: a light source inserted in the hollow portion in the in-mouth insert for irradiating light on the upper jaw dentition and the lower jaw dentition through the light-transmitting portions; a pair of reflection mirrors for reflecting the light from the upper jaw dentition and the lower jaw dentition toward the outside of the in-mouth insert; a scanner for moving the light source and the pair of reflection mirrors along the depth direction of the hollow portion of the in-mouth insert; and an image pick-up optical system for receiving the light reflected by the pair of reflection mirrors.
According to the above arrangement, since the light-transmitting portions are respectively provided on the front and back sides of the in-mouth insert and the image pick-up optics have the light source inserted in the hollow portion in the in-mouth insert for irradiating light on the upper jaw dentition and the lower jaw dentition through the light-transmitting portions and a pair of reflection mirrors for reflecting the light from the upper jaw dentition and the lower jaw dentition toward the outside of the in-mouth insert, the upper jaw dentition and the lower jaw dentition can be simultaneously taken by a single scan. Further, since the positional relationship between the upper jaw dentition and the lower jaw dentition can be accurately obtained, the positional relationship between the upper and lower bite surfaces can be accurately grasped.